Medical ventilators may determine when a patient is connected to the system in order to deliver specified therapy and synchronize the operation of the ventilator with the natural breathing of the patient. During ventilation, certain levels of leak rate may be unavoidable or allowed and this should not prematurely result in a patient disconnect determination. Furthermore, it is now common for medical ventilators to compensate for leaks in the ventilation system in order to accurately synchronize the therapy with the patient's breathing cycle as well as provide therapy that compensates for the leaks.
Detection and declaration of the disconnection of a patient from the ventilation system during therapy is a feature provided by some ventilators. Some ventilators are provided with a disconnect alarm that notifies caregivers when a patient is no longer connected to the ventilation system. Depending on how a ventilator compensates for leaks, this can impair the ability of the ventilator to accurate detect patient disconnect and provide an alarm to caregivers while allowing unimpeded therapy under acceptable leak conditions.